N = input()
 
A = int(N)
 
if A>=30:
  print('Yes')
else:
  print('No') N = input() N input() input A = int(N) A int(N) int N if A>=30:
  print('Yes')
else:
  print('No') A>=30 A 30 print('Yes') print 'Yes' print('No') print 'No' A = int(N) int(N) A N = input() input() N
N = input()
 
A = int(N)
 
if A>=30:
  print('Yes')
else:
  print('No')